keep (someone) on retainer

Translations
держать (кого-то) на удержании
The lawyer was kept on retainer by the company for any legal issues that might arise.
Адвокат был оставлен на удержании компанией для решения любых юридических вопросов, которые могут возникнуть.
Definitions
To keep someone on retainer means to pay them a fee in advance to ensure their availability for future services or advice, typically in a professional context such as legal or consulting services.
Words
retainer

noun
фиксатор
keep

verb
держать